... expressed as following: Q = K1 * N P = K2 * N2 PW = K3 * N3 N-speed Q-flow pump outlet pressure P ... -PW-shaft power K1, K2, and K3-constant as shown ... following diagram. Suppose a water pump, the rated power is PW, rated outlet pressure is P, and the rated flow ... is Q.Then produce the rated flow, shaft power: PW = K * P * Q Where K is a constant, through ...